Audience measurement of media content (e.g., broadcast television and/or radio, stored audio and/or video content played back from a memory such as a digital video recorder or a digital video disc, audio and/or video content played via the Internet, video games, etc.) often involves collection of content identifying data (e.g., signature(s), fingerprint(s), embedded code(s), channel information, time of consumption information, etc.) and people data (e.g., identifiers, demographic data associated with audience members, etc.). The content identifying data and the people data can be combined to generate, for example, media exposure data indicative of amount(s) and/or type(s) of people that were exposed to specific piece(s) of media content.
In some audience measurement systems, the collected people data includes an amount of people being exposed to media content. To calculate the amount of people being exposed to the media content, some measurement systems capture a series of images of a media exposure environment (e.g., a television room, a family room, a living room, a bar, a restaurant, etc.) and analyze the images to determine how many people appear in the images at a particular date and time. The calculated amount of people in the media exposure environment can be correlated with media content being presented at the particular date and time to provide exposure data (e.g., ratings data) for that media content. Additionally, some audience measurement systems identify people in the images via one or more identification techniques such as, for example, facial recognition.